Spark-plug.



J J- HAGEN. $PARK PLUG. APPLICATION FILED SEPT. 26.1912.

Patented N0v.3,1914.

v E y k m 4. PP a however, there is sufiicient deposit or oil aud carbon between all of the terminals of the electrodes 5 and the outer electrode surrounding them to prevent sparking between these members, a spark will be produced between the inner ends of the electrodes 5 and the rib 6, at whichpoint the parts are much less susceptible of accumulation of oil and carbon produced in the cylinder of an explosive engine supplied with rny spark plug.

I claim A spark plug comprising an outer tubu lar electrode having an internal rib intermediate of its ends, an inner electrode stem extending longitudinally within said outer tubular'electrode, and a plurality of electrodes carried by said stem, the said electrodes including primary spark terminals arranged at difi'erent sparking distances from said outer tubular electrode aside from said internal rib, and having secondary spark elements located opposite said internal rib and at a greater distance therefrom than the distance between any of said primary spark terminals and said outer'electrod'e.

JOSEPH J. HAGEN.

In the presence ofv A. J. MGOAULEY, E. B. LINN. 

